1. Field of the Invention
The present invention relates to an electronic device such as a personal computer which functions to calculate and display a matrix. More particularly, the present invention relates to an electronic device which can display a matrix in a row-column format as generally written in ordinary text books.
2. Description of the Prior Art
In order to calculate and display a matrix, an operator must first input each value of the elements of the matrix to such an electronic device. FIG. 16 shows one example of a conventional format of a matrix displayed on a screen portion 60 of a display apparatus, during an input operation for inputting each value of the elements of the matrix by an operator. As shown in FIG. 16, the electronic device displays "MAT A" indicative of a matrix A according to the input operation. In this example, "341." is input as a value of a first-row and first-column element of the matrix A denoted by "A(1, 1)". "12.3" is input as a value of a second-row and first-column element of the matrix A denoted by "A(2, 1)".
During the input operation, the matrix A is displayed in the conventional format, as shown in FIG. 16. However, the calculated result of the matrix A is displayed in the row-column format, as given by Expression (1). ##EQU1##
FIG. 17 shows an exemplary expression including the matrix A displayed on the screen portion 60 (hereinafter, such an expression including a matrix is referred to as "a mixed expression"). Conventionally, a mixed expression is displayed as a character string "1+MAT A*6" in a simplified manner. In other words, the matrix A cannot be displayed in a row-column format in the mixed expression. Only the calculated result is displayed in the row-column format as given by Expression (2). ##EQU2##
As described above, the electronic device of the prior art displays a matrix in the conventional format during the input operation. Therefore, it is difficult for the operator to recognize which value corresponds to an element of the matrix during the input operation. As a result, since the input operation requires a long time, there exists a problem that many mistakes are easily made.
The calculated result or the like is displayed in the row-column format. However, if the size of the resulting matrix is larger than that of the screen portion 60, there is no symbol on the screen portion 60 for indicating that at least one element of the matrix is off the screen portion 60. Therefore, it is difficult for the operator to recognize which part of the entire matrix is displayed on the screen portion 60. Because the matrix cannot be displayed in the row-column format in the mixed expression during the input operation, the input operation is difficult and complicated, which prevents the electronic device from being improved in operability.